[The role of temperature in the preparation of cardioplegic solution for the heart open surgery].

There was compared the occurrence frequency of the acute cardiac insufficiency, acute myocardium infarction, acute disorder of cerebral blood circulation, disorders of cardiac rhythm and conduction and other perioperative complications in patients of three groups, operated on using artificial blood circulation, in whom the cardioplegic solution, prepared according to different methods, was used. It is recommended not to permit the crystallization (freezing) of isotonic sodium chloride solution occurrence, used for cardioplegia and for flooding to the pericardium cavity also to cool the heart externally.

[Changes in chromatin conformation induced by ionizing radiations with different LETs in resting and proliferating hepatocytes from rats of different ages].

The method of flow cytometry was used to study conformation changes in rat hepatocyte chromatin exposed to various doses of X-rays and fission neutrons (mean energy of 0.85 MeV). Chromatin decondensation induces by both X-rays and neutrons was shown to be a function of dose.

[The effect of inhibitors of DNA topoisomerase II on the radiosensitivity, repair and conformational changes in the chromatin in mammalian cells].

A comparative study was made of modification of the effects of UV-, X- and fission neutron-radiation by DNA-topoisomerase II and spermidine. The efficiency of the studied agents was the highest with UV-radiation of cells. Being insignificantly efficient in changing the radiosensitivity of cells, novobiocine and spermidine suppressed significantly the recovery of cells from radiation damages which were realized as chromosome aberrations upon X-ray dose fractionation.

[The modification of the radiation damage to the chromosomes in the somatic cells of radiosensitive Drosophila mutants. The radioprotective action of cysteamine].

The radioprotective effect of cysteamine has been studied in larva nerve ganglia of the radiosensitive mutant rad(20)201G1, mutagen-sensitive mutant mus(2)201G1 and the control strain of drosophila. Cysteamine was shown to produce a radioprotective effect in somatic cells of mus(2)201G1 and the control strain of drosophila which was manifested by the decreased incidence of cells with chromosome aberrations and diminished yield of deletions and exchanges. No significant radioprotective effect of cysteamine was observed in somatic cells of rad(2)201G1 mutant.

[The modification of the radiation damage to the chromosomes in the somatic cells of radiosensitive Drosophila mutants. The effect of fractionating the gamma-ray dose].

A study was made of the effect of gamma-ray dose fractionation registered by chromosome aberration induction in somatic cells of the mutant rad(2)201G1, the mutant mus(2)201G1, and the wild type strain of drosophila. The dose fractionation upon irradiation of the mutant mus(2)201G1 and control strain larvae was shown to decrease the frequency of cytogenetic damages to cells. In contrast, when the radiosensitive mutant rad(2)201G1 was exposed, the effect of dose fractionation was insignificant.